Age and Rate of Accumulation of Metal-Rich Hydrothermal Deposits on the Seafloor: The Lucky Strike Vent Field, Mid-Atlantic Ridge

Dennis Sánchez-Mora , John Jamieson , Mathilde Cannat (1) , Javier Escartín (2) , Thibaut Barreyre

1 IPGP (UMR_7154) - Institut de Physique du Globe de Paris
2 UPCité - Université Paris Cité

Hydrothermal venting at the Lucky Strike hydrothermal field, located on the Mid-Atlantic Ridge, is associated with faulting linked to the tectonic dismemberment of a central axial volcano. Radium-226/Ba dating of hydrothermal barite indicates that hydrothermal venting is at least 6,600 years old, and that Lucky Strike is one of the youngest known vent fields on the Mid-Atlantic Ridge, which typically have ages exceeding 20 ka. Deposit volume calculations indicate that the total accumulated mass of the hydrothermal deposits on the seafloor at Lucky Strike is ∼1.3 ± 0.2 Mt, and that this mass accumulated at a maximum average rate of 194 ± 28 t/yr. This accumulation rate is comparable to other well characterized mid-ocean ridge hydrothermal sites, such as TAG and Endeavor, but at Lucky Strike is concentrated within a relatively small area of <2.5 km².

Mots clés: lucky strike; seafloor massive sulfide deposits; hydrothermal; geochronology; mass accumulation rates; mid-ocean ridges

Domaines: Planète et Univers [physics]; Sciences de la Terre

Dennis Sánchez-Mora, John Jamieson, Mathilde Cannat, Javier Escartín, Thibaut Barreyre. Age and Rate of Accumulation of Metal-Rich Hydrothermal Deposits on the Seafloor: The Lucky Strike Vent Field, Mid-Atlantic Ridge. Journal of Geophysical Research : Solid Earth, 2022, 127, ⟨10.1029/2022JB024031⟩. ⟨insu-03748525⟩